This invention relates to polymers prepared from monoarylcyclobutane monomers.
Thermoset resins are compositions which can solidify irreversibly upon heating. Such resins are useful in many engineering applications such as, for example, coatings, structural laminates, adhesives, films, composites and the like. Examples of conventional forming techniques are transfer molding, compression molding and hand-laying processing.
Desirable thermoset resins possess chemical resistance, tensile strength, temperature resistance, electroinsulative or electroconductive properties and other properties which encourage their use as engineering materials. Such properties depend on the chemical structural of the resin or materials added to the resin. For example, resins comprised of aromatic structures, especially aromatic polyamides and polyimides intrinsically possess thermal and oxidative stability. Unfortunately, the preparation and curing of such resins require the handling of highly toxic and volatile compositions. Furthermore, the resins are difficult to form in molding processes and are at times undesirably insoluble in many organic solvents.
Another class of engineering polymeric compositions are thermoplastic polymeric compositions. Such compositions soften upon heating and can be formed into many useful shapes. Upon cooling, the composition is hardens to desired shapes. Advantageously, the polymeric compositions exhibit chemical resistance and are structurally durable. Examples of suitable thermoplastic polymeric compositions are those prepared from polycarbonate thermoplastic compositions.
In U.S. Pat. No. 4,540,763, poly(arylcyclobutene) polymers are disclosed. Such polymers are prepared from monomers which contain at least 2 arylcyclobutene moieties per monomer. The polymers exhibit excellent mechanical and physical properties such as high strength, thermal stability and glass transition temperatures. Unfortunately, because of the thermosetting nature of the polymers, the polymers are difficult to process in compression molding processes.
It would be desirable to have a new class of polymeric compositions which could exhibit the thermosetting or thermoplastic properties and which could be polymerized with thermosetting polymers to impart processing advantages such as compression molding capabilities.